After traveling with the Doctor for some time, Ben believes he was becoming unfit. He says the moment the Tardis materialises he is going outside to jog. So the Doctor, amused by this types in some random coordinates into the Tardis. They land on a planet with a rocky terrain with loads of mountains and a green sky. With the conditions outside ok, Ben wastes no time and heads off away from the Tardis on his jog.

The Doctor and Polly knowing it not safe to leave Ben on his own out there, decide to follow him by walking. While on their journey Ben disappears from sight as he passes a small mountain. Once The Doctor and Polly reach the point where Ben disappeared they discover a huge mechanical Grasshopper like creature. The Doctor knowing itís mechanical, therefore a robot, determines itís being controlled from a control point.

He sees an opening in a rock, he deuces itís the opening to an underground settlement. He suddenly had a thought. Picking up a rock he quickly flings it at the opening. But the robot is too fast and swallows it. Polly now gets the idea that this has happened to Ben, he has been swallowed up by the robot. The Doctor and Polly rush back to the Tardis while being pursued by the mechanical Grasshopper. Once inside the Tardis, the robot begins hitting the blue box.

To the astonishment of the Doctor and Polly, Ben is inside the Tardis. He had returned from his jog to find no one here. With the Doctor knowing heís safe and sound, he begins to dematerialise the Tardis, escaping the giant mechanical Grasshopper.

Time-Placement: Ben states he hasnít gotten any exercise since traveling with the Doctor. Meaning Ben and Polly have been traveling with the Doctor for a while. Placing it to the near to the point where they meet Jamie.

The Doctor had been working at the factory for a week now. His main job was to turn small wheels to reduce pressure. He dared not stop or he would receive an electric shock that might kill him if he received too much. He worked in the same room with two other people named Ben and Polly. They were expected to work all day, have an evening meal, and expected to go to sleep until getting up the next morning to perform the same work. If they did not sleep at night they would get terrible nightmares, which could send people mad.

On one particular day a Technician came up to him and said he had switched off the monitor on the Doctorís, Benís and Pollyís machine. He explains they know the Doctor is not from the planet Doranda and how they came in the Tardis. He says they must help him and offers them each a helmet, which will stop them dreaming and having nightmares. Very quickly their minds start to clear and they begin to remember who they are. Their minds had been brainwashed to ensure they would work.

The Technician tells them he will meet them in the night. So at night they wait for him. When he finally arrives he takes them away to a control room where several brains lay in tanks of water. The technician explains that they were invaders who took his planet and made his race work in these factories. He goes on to explain none of them are allowed onto the surface, some of his race have even be born in the factory itself.

He asks the Doctor, Ben and Polly to stop the life support which keeps the brains alive. The Dorandains cannot do it themselves because the brains are able to stop them with telepathic powers. The Doctor refuses saying he cannot kill them, it is against his nature. However the Technician shows how much the brains have made his race suffer and the Doctor turns off the life support machine destroying the brains.

The Doctor, Ben and Polly arrive on a planet where blonde haired people are inferior to dark haired people. The Doctor, believing that the people with blonde hair are too intelligent to be slaves, speaks out to the ruler of the planet. He tells the Doctor they will set the blonde hair people free if they can pass the two tests of Trufes.

The first test is where one of the fair-haired people has to swim across a lake to an island and swim back again. But there are crocodiles that could possibly attack him. So the Doctor knocks them out with a stun blast allowing the blonde hair man to complete the challenge. The Second challenge is a game of tug of war between the blonde haired people and the dark haired people. The outcome is the blonde haired people win and they are no longer slaves.

The Doctor had landed on a dark and miserable planet. He was desperate to explore it but was unsure due to the never-ending rain. But soon he could wait no longer for the rain to stop, and headed out to explore. It was only a few steps that he discovered it would be better to explore the planet in the morning rather than in the darkness of night. Just as he was about to re-enter his Tardis he was pushed in by two tall looking men in cloaks. They said to the Doctor that he was late, and he had to go with one of them (Zvar) to meet Qar. Obviously the Doctor knew the two had mistaken him for someone else, but he played along.

So the Doctor went with Zvar while the other stayed to guard the ship. The Doctor was escorted to a small spacecraft and entered in along with Zvar. Zvar started up the craft and in no time they were flying. He turned on the scanner showing the Doctor the Tryods. They were yeti like creators with huge black bulges on the back of there heads. These bulges were organs, which allow the Tryods to heal if they have been fighting, and only when the organ is damaged can they die.

Once they arrived at a palace the Doctor meets Qar, she asks him whether they have permission from Raymah to begin the Massacre! She explains the Massacre is exterminatiom on the plateaus and hills so they can collect the minerals, which lie beneath the soil. Qar is confused at the fact that the Doctor looks nothing like Raymahís messenger Asiries. Suddenly they get a message that Asiries has just landed and that the Doctor is an impostor.

So Qar instructs Zvar to take the Doctor back to his Tardis and make sure he leaves and never comes back. Zvar takes the Doctor back to the craft of which they arrived. The Doctor did not want to leave but was forced to at gunpoint. Once they landed Zvar forced the Doctor down to the floor. He has decided to kill the Doctor by attaching him to the wall of a cave, which is a popular place for Tryods. The wall has a special adhesive that cannot be escaped from unless a special solvent is applied.

Once left on his own, the Doctor is discovered by Asiries who helps the Doctor escape by using his laser gun to burn the Doctor off the wall. Suddenly a Tryod enters the cave and almost kills Asiries, but luckily the Doctor manages to push him out the way. They escape from the cave and head for the Doctorís Tardis. Asiries is grateful to the Doctor for saving his life and he promises he will try to persuade Raymahís decision against the Massacre. Once they arrive at the Tardis Asiries manages to get the guard away from the Tardis allowing the Doctor to enter. The Tardis leaves the planet and thatís when the Doctor recognises it. The planet is Paxltt, he had been here before in the future knowing that the hills and the plateau were not destroyed. Asiries had kept his word.

Time-Placement: After The Tests of Trefus, although no explanations are given about the absence of Ben and Polly.

Ben had finally started getting used to the fact that the Tardis was a time machine shaped like a police box. He looks at the visual monitor to see in horror a hundred star ships heading towards earth! The Doctor says that thanks to a device he has been able to uncover that they are ships from the planet Arcturus. The Arcturians have two extra arms but besides that they are similar to humans. They are a warlike race that hope to take over the earth really quickly.

Polly points out that because the visual scanner is giving off an electric pulse the ships should be able to see them. The Doctor confirms this as very quickly one of the ships has engulfed them into their hanger. They step out of the Tardis to find a group of small aliens with wings, claws, and webbed feet.

They explain that they are from Arcturus but their planet had started to lose its atmosphere, which would have meant no air to breath and no sky to fly in. So instead of waiting for a slow extinction they decided to leave their home world and find a new one they could fly in. However it has taken them Forty Five Light-years to get to earth and only recently have the original Arcturians who remember the planet have died. They have also forgotten what some of the buttons on the ship do because they were not taught.

The Doctor, satisfied they are not aliens bent on taking over the world discovers a new problem. That the human race will think they are invaders and will try to destroy them. So the Doctor decides to help them by altering their time coordinates. He sends them to the Ninth Dimension were the are assured to find a world they can call there own.

Time-Placement: After The Word of Asisiries. Ben states he has only just gotten used to the Tardis, and the Doctor states he has only just regenerated, confirming the placement of these stories at the start of the Second Doctor's adventures.

The Doctor, Ben and Polly land on a planet, which to Polly, looks like Heaven. While looking at the surrounding area they met six people, three woman and three men. They greet the Doctor and his companions cheerily and tell them they have landed on the planet Harmony.

The inhabitants take them back to their city and invite them to eat at a banquet where the only food served is fruit. The Doctor can't understand how the people of this planet, who all look very healthy, can survive simply on fruit. However the people of this planet say they have no need for meat.

Once the banquet is over they are taken to some sleeping quarters to rest. However the Doctor feels uneasy about the place and decides to do some snooping around on his own. He discovers a room full of heads, which are neatly set in cabinets.

He hears two people go past and listens closely. He then discovers that they actually eat people who land on the planet. They intend to use the Doctor's intelligence first to boost their technology and then eat. As for Polly and Ben, they will be kept in the breeding pen. The idea of them being eaten, terrifies the Doctor and he knows they must get off this planet quickly. However, his disappearance from the sleeping quarters hasn't gone unnoticed and soon a full search operation to find the Doctor is on the way.

Just as he reaches the sleeping quarters, he is jumped upon by several guards. He remembers from the banquet that he played his flute and the sound hurts them. So he blows some tunes out of his flute and he is able to escape whilst the others are in agony.

With this chance he grabs Ben and Polly and take a ship heading back to the Tardis, escaping Harmony

There was something wrong on the Tardis monitor screen. There were no stars, just blackness, nothing else. They had landed in between the part of space linking from their universe to another. The Doctor, curious at where they had landed in wanted to explore what was outside.

After persuading Ben to come with him, they both set off space exploring into the darkness, whilst Polly waits in the Tardis. After a few minutes, Polly says that the biological probe on the Tardis has picked up something moving. The Doctor explains that it is him and Ben she is picking up, but Polly is convinced that there is something else out there with them.

Suddenly they spot some lights in the distance coming closer towards them, this means there is something else here in space stuck with them. Gradually the object gets closer until they can finally work out it is a giant sphere. There are opening in the sphere, and after some persuading, the Doctor and Ben venture inside.

In the interior they find several cocoons. All have frozen aliens inside them, and some are coming out of the cocoons. They have several limbs and a row of eyes. The Doctor insists they couldn't be alive but in suspended animation.

He is so mesmerised by the aliens that he doesn't truly notice that they're no longer asleep, and they begin to move and break out of their cocoons. Ben grabs the Doctor and hastily drags him out of the Sphere and into the Tardis.

Quickly, Polly has managed to get the Tardis back into their own universe. The Doctor becomes angry at the fact he was dragged away from such fascinating creatures, but Ben points out that they had no idea whether they were hostile or not. In the end, the Doctors accepts that they where right to take him back to the Tardis and is amazed that Polly was able to control the Tardis.

The Doctor, Ben and Polly land on the planet of Light. It is called this because of its two moons, which keep the planet lit on a twenty-four hour basis, meaning they have no nighttime. However the planet is in grave danger.

A man called Igor, an ancient who works at the planet's observatory, tells the Doctor that an eclipse is coming. It will plunge the world into darkness. When this happens, the people of the world will go mad with fear.

It is something that has happened every three hundred years on the planet, and it will happen again. Once the people go mad, they will inadvertently destroy the world. Igor, insists that the people will not believe the idea that darkness will drive them to death, and are beyond savour.

However he tells of an underground tunnel where several children lie in a deep sleep. He asks the Doctor to give the children some notes, which will allow them to prepare for the next eclipse.

After their meeting with Igor, the Doctor, Polly and Ben watch from the Tardis, as the planet of light falls into darkness, and begins burns. However, the Doctor is sure this will be the last time the planet will have to suffer.

The TARDIS materialises on board a ship. Through the scanner the Doctor, Ben and Polly are able to discern the sails of a fleet as well as seeing and hearing the guns and canons firing. The Doctor suggests continuing on their way but Ben is eager to see what a ship in battle was like in history. Polly merely feels sick.

They step out onto the deck and are promptly accosted by a sailor and taken to a mast where they are tied up. Be notices from a plaque that they are aboard the H.M.S. Victory. Polly assumes that this is the Battle of Trafalgar. When they are questioned by a naval officer he presumes that they are French or Spanish spies and says that they shall be hanged. Their presence attracts the attention of the ship's captain, Hardy, and the Admiral of the fleet, Lord Nelson. Hardy wants the trio to be thrown overboard but Nelson is intrigued by them, amused even, when the Doctor says that he is an astrologer who has arrived here by accident.

When Nelson says that he expects every man to do his duty Ben urges him to fly that message on the ships flags. Nelson agrees that this would be a good idea. He asks Ben what he does and Ben replies that he is a sailor, previously on the Indefatigable but now on the H.M.S. Tardis. The Doctor tells Polly that he intends to change history this day and tries to get Ben to pick up a musket and shoot the man who would kill Nelson. Unfortunately, Hardy thinks that they are trying to assassinate Nelson and has them captured again. As the ships swing into the battle and the canons roar again the travellers escape back into the TARDIS where they see Nelson's demise on the scanner.

The TARDIS lands in darkness. When Ben steps out he says it is like a grave. The Doctor joins him and agrees that it is, in fact, a grave. Specifically, it is an Egyptian pharaoh's tomb. This relieves Ben and Polly: the long dead don't scare them. The Doctor says that the pharaoh isn't long dead since the grave hasn't been ransacked they are in a time some thousands of years before Ben ad Polly's birth. Because the air is so fresh the Doctor suggests that the tomb may have only just been sealed.

Polly looks around with wonder at the piles of gold and jewellery and suggests that they help themselves: nobody would be any the wiser. The Doctor is horrified at the notion. He begins to think that they are in the tomb of Tut-Ankh-Amen. Just then, Ben hears a sound. The noise gets louder and begins to sound like the work of men with spades and picks. The Doctor is puzzled because the tomb of Tut-Ankh-Amen was undiscovered until 1923. As the diggers break the wall nearby, Polly's screams bring the work to a halt. Ben thinks that it is time to go back to the TARDIS but the Doctor wants to protect the treasures from grave robbers. Ben reluctantly agrees and sends the Doctor back to the TARDIS with Polly. He then picks up the golden face mask of the pharaoh.

When two grave robbers burst in through the wall they are met by the sight of the dead pharaoh walking towards them. They flee in terror, bringing down a huge rock fall on the way out. Ben makes it back to the TARDIS and the ship takes off again.

The TARDIS lands on a planet somewhere in the Milky Way and the Doctor, Jamie and Victoria step out. Immediately, the Doctor warns them that they are in the middle of an interstellar conflict and that they should get back into the TARDIS. Before they can react a violet beam engulfs them and lifts them through the sky, TARDIS and all. They see energy beams and vast space ships engaged in combat before they are deposited within an airlock.

The aliens that greet them are hideous, vaguely humanoid in shape but with silver scales and tusks. As soon as the Doctor says that they are from Earth, the aliens draw their weapons and say they will be taken to the Supreme Lizard as spies.

The Supreme Lizard is in the hatchery. He is annoyed at the intrusion by the three travellers and uses rays from spouts in the corners of the room to freeze them rigid. When he is informed that they are from Earth he grows more interested. His Saurians have never caught a Man from Earth before. He says they will be dissected by his scientists. It seems that the Saurians have been using cosmic rays as weapons in a century's long war to make themselves the Lords of the Galaxy. The only planet to hold out against them is Earth which has the ability to make itself invisible and reappear at other parts of the galaxy. The Doctor claims to know nothing of this since he has not been on Earth for thousands of years.

The Saurians apparently think the TARDIS is the Doctor's robot so he tells them that if the lizards let him free he will use his robot to give them the secret of invisibility. This apparent cowardice angers Jamie but convinces the Supreme Lizard, Lord Haxtl. As soon as they are free of the beams the trio run into the TARDIS. The Doctor tells Jamie that, from the sound of it, Earth is the true Lord of the Galaxy.

The travellers are looking at the TARDIS scanner. They watch a column of well-muscled men marching by the ship but there is something unusual about them: they hardly seem to be moving. Jamie asks whether the Space-Time Visualiser is 'on the blink'. The Doctor denies this but is perturbed by something, particularly when he sees a low-lying cloud which he says is impossible in such an atmosphere. Victoria is disappointed because she thinks that they won't be able to leave the TARDIS. However, the Doctor assures them that they can go outside. He particularly wants to investigate the cloud which is growing larger. He reveals his Floater; an inflatable flying craft of his own invention.

Jamie asks if they can get closer to the army of men so the Doctor swoops the Floater across the rolling dunes towards them. The men, each well-armed and eight feet tall, seem oblivious to the newcomers. The Doctor lands the Floater and he and Jamie stand in front of the column. The army carry on marching and Jamie dives out of their way but the Doctor stands his ground and the army passes through him. Jamie looks on in wonder as the men enter the cloud which now resembles a giant crystal ball containing an image of a city. The Doctor surmises that this is an echo through time of a great event in the planet's past. Jamie is eager to photograph the city and, despite the Doctor's warnings, runs into the cloud.

At first the city is faint like a mirage. Jamie wanders round in a daze until there is a tremendous noise and he collapses. When he wakes he is on the stone floor of a temple and surrounded by the army of men. One says that the alien that fell from nowhere is awake and sends for Ziita. Ziita is apparently their leader, a huge man with a scar across his face. He says that the arrival of a white-skinned alien is a sign from the God of War and says that Jamie will lead them into battle against the Scythias. Jamie is panicked but Ziita says the Scythias will flee when they see him because they know the prophecy, too.

In fear, Jamie darts away from the men and runs out of the city across the dunes. He is horrified to see that he is running straight towards the Scythias who resemble monstrous slugs. Realising that he is about to be caught in the cross fire of battle he dives into a shell-hole. Suddenly the cloud appears again and he runs into it. The Doctor is waiting for him and pulls him out to safety. The Floater is nearby and Victoria is worrying about him.

No sooner has the TARDIS landed in a corridor containing thousands of cubicles than the three travellers are put into a hypnotic trance. As they are placed one in each of three cubicles they hear their captors enter the TARDIS and examine it. Meanwhile the trio are wired up to devices that record their thoughts and play them back on a screen in front of them. The Doctor knows that these thoughts are kept by the Masterminds of Space and Time and will help to create an Encyclopaedia of the universe.

To combat the process the Doctor concentrates on remembering every scientific theorem that he can, followed by images of all of the horrors he has witnessed (and some that he has imagined). Finally he lets his mind go blank and concentrates on the screen itself until it is filled with ever-diminishing images of itself.

The screen explodes into a pattern of vivid colours and he is free to move. A voice in his head instructs him to come to the masters. He walks past the cubicles, looking in on creatures the like of which even he has never seen. The voice in his head says that it is the Doctor's ability to think of nothing that intrigues them. They release Jamie and Victoria, too, since the Masterminds sense that the companions are integral to the Doctor's life. As they walk through the corridor the Doctor warns his friends that their every thought is still being monitored.

At the end of the corridor a hole opens out onto Space. There are no stars, only total blackness. In the dark are seven lights. The voice explains that these are the Masterminds. Each one represents the thoughts of millions of their people and they are made of pure energy. It tells of how they were once people with physical bodies but millions of years ago they gave this up and became the pure energy forms. The voice says that they can create physical environments at will, such as the place where the travellers are standing. It adds that the Masterminds have grown bored. Realising that they have come to the end of their ability to evolve, they are going to return to the physical world.

The Doctor dismisses this notion as fantasy but Victoria says she feels sorry for the seven. They are intrigued by her compassion and try to learn more of her selfless emotions. The Doctor picks up an idea, presumably from the seven, that they are fashioning a whole galaxy in the far flung corner of the universe which they intend to people with creatures the like of which they have been learning from. The Doctor tells Jamie that Victoria might help them create a human race born out of compassion and fellow-feeling. She tells them that love is the most important emotion of all.

The Masterminds say that they have learned enough and will return all of their specimens to the place from which they were taken. None of them shall remember their experiences. The only creature they will keep will be Victoria and they shall name their galaxy after her. Victoria says that this would be a bad start: she belongs to the Doctor and nobody should be forced to do something that they don't wish to. The seven agree.

Back in the TARDIS, the Doctor tells Victoria that she should be proud to have a new galaxy named after her. She and Jamie stare at him blankly and the Doctor dismisses it as a vivid dream he had.

The TARDIS lands in what seems to be a giant's toyshop. The dolls are six feet high and the jack-in-the-box that scares Jamie is ten feet tall. The Doctor is delighted by their find and insists on riding round on the model railway. Victoria screams at the teddy bear until she realises that it is just a toy. The only puzzle is that the construction sets seems to have been used recently: half-finished models are strewn across the floor. Their favourite toy is the doll's house. It is almost as large as a real house and all three of them enter. While Jamie and Victoria walk in easily, the Doctor has to stoop. The others stay downstairs with the plastic 'family' and the Doctor goes up to one of the bedrooms. Inside is a table with a doll's house - the exact replica of the one that they are in. The Doctor feels faint and steps towards the table but it has been replaced by a house as big as the one he just entered. He enters and wonders if the other two are upstairs.

There is a dry, crackling sound. He turns and tries to open the door but it won't budge. When he turns back he sees a doll's house, another identical replica, on the floor. He tries to count how many houses: the one he went into with the children, the one he just entered, and now this. He realises that this is all like a dream but it seems pleasant enough. However, the family in this house the family in the chairs seems too lifelike. There is a wind whistling outside, the floorboards creak. It is all very disconcerting. Outside is the sound of laughter, or maybe thunder.

Filled with insatiable curiosity he enters the new doll's house. The whistling and creaking intensify and makes his way upstairs to find the next house. This one is bright and full of light. He feels happier again and thinks that the doll family look even more real than ever. From somewhere comes the sound of children laughing and playing. He wonders where the people making the noise can be. The next doll's house grows up before him and he instinctively enters. This one is almost pure light.

The Doctor yearns to go on into the infinite universe, exploring ever deeper into the houses, but he knows he must get back to Jamie and Victoria. He runs back through the doors, down through the stairs, exiting one house after another until he leaves the final house to find his companions playing in the toyroom. Victoria comments on how ill he looks but he brushes this aside. Later, after they have left, he sleeps a dreamless sleep but wakes with the memory of his regret.

When the TARDIS lands it tilts alarmingly and the screens show that it is on the back of a huge dinosaur. Victoria demands that they dematerialise again but before they can the TARDIS topples off. It lands upright and the scanner shows them the huge size of the monster, which the Doctor says evolved from the dragons that once lived on the planet, before it slides off into the sea.

Impetuously, Jamie opens the door to find that they are adrift on some pack ice. He also discovers that he can't breathe. He staggers back inside where the Doctor reprimands him before providing all three of them with Atmospheric Density Jackets. Once more they leave the TARDIS. The Doctor tells them that the 'water' around the ice is acid. He gives them contra-gravity belts and together they fly over the sea towards jagged rocks in the distance. They are attracted by a loud clashing noise and find an arena where soldiers are fighting another dragon in front of an audience of mantis-like creatures. The dragon kills some with its fiery breath but others shoot it with missiles fired from crossbows. It ides in agony as the missiles blow it apart. Victoria is horrified by the sight. As the travellers turn to leave they are dragged down by a searchlight that combats their contra-gravity belts.

A bird-faced alien demands to know who they are. The Doctor tells him that their space ship landed in the sea nearby. They are dragged from the arena to meet the Manti leader. He says his scout ships have not found a space ship on the ice and says that they must be Imiga pirates. They are taken to a pit containing another dragon. The Doctor is thrown in. As the dragon closes in on him he pulls out his recorder and plays a tune. The dragon is enthralled and follows the Doctor out of the pit. The soldiers panic and flee, leaving the travellers alone. They leave the area, deserted now after everybody else has run away.

They make it back to the mountains and are about to begin the climb to get back to the sea when they hear a noise from a cave. A group of humanoid birds are standing around the TARDIS. The Doctor says that these must be the Imiga pirates who have stolen the ship. He gets Jamie and Victoria to loosen some boulders to cause a landslide. This makes the pirates run out of the cave and the three travellers run in and enter the TARDIS.

The TARDIS lands on a planet where the seas have dried to great salt plains. On one continent there is only a single, cathedral-like building. Inside the vault of this building are thousands of people lying in glass cases. Jamie and Victoria think that they are dead but the Doctor says that this is a rogue planet, travelling from a distant galaxy. At the end of the vault is an altar with a lever like an ankh. The Doctor pushes the lever towards an Egyptian hieroglyph for 'life'. The people in the cases begin to revive almost immediately.

They climb from their caskets and as one they kneel and sing a hymn to the three travellers. Jamie and Victoria retreat behind the altar but the Doctor approaches the throng who back away in fear. One of the people, dressed like the others in metallic robes, says that the newcomers are gods of destruction. He says that his people are Salonians, survivors of a great war who fear the retribution of their enemies. The Doctor insists that he is not a god, merely a traveller in time and space. The Salonian says that his people destroyed half the world, Axal, in the war and then fled into their chambers when the sun went nova. He now thinks that the Doctor is a demon for waking his people from their peace.

The Doctor takes him to a door and shows him the barren world outside. The Salonian thinks that their enemies, the Colonians, must have returned and destroyed the city. The Doctor tries to argue against this but the throng race down to a flight of stairs behind the altar. Below ground are huge missiles which they intend to use in a counter-strike. The Doctor sees his friends at the top of one of the missiles. Jamie calls down that they were sitting on the floor, resting, when the missile rose up from beneath them. The chief Salonian says that the Doctor will travel with him to witness the end of the Colonians.

Jamie and Victoria are brought down and go with the Doctor into a passenger rocket. The Salonian crew flies the rocket to the Eastern Continent where they expect their enemies to be. Instead, all they find is a sea of glass. The Salonian leader remembers that a huge cobalt missile strike was launched against their enemies and that the crew of the reconnaissance ship reported the complete destruction of their enemy before shooting themselves.

Victoria comments that there were warnings that such a thing could happen on Earth. The Doctor speculates that this planet is Earth. As he returns to the TARDIS with his companions the Salonians return to their caskets. The leader pushes the lever back to 'rest' and then shoots himself.

The Doctor decides to shrink the TARDIS so that it can materialise on the nucleus of an atom. To the travellers it appears that they are on a rocky planet. The Doctor, Jamie and Victoria set out to explore and discover a tree hanging which is bearing teardrops. One of the drops has a face which tells them that they are in the Uranium Universe. The problem is that some of the other worlds in the universe have been destroyed in explosions that destroyed entire civilizations. The civilization of this world has been able to manipulate space and time and relocate within indestructible teardrops.

The Doctor says that the Earthlings have recently discovered atomic power, using uranium. The planet's impending destruction in an explosion forces the travellers to leave. Victoria wants to return to Earth to tell the people not to use atomic power but the Doctor replies that her words will fall on deaf ears. He also suggests that the universe as we know it might be made up of atoms in a larger universe. On that psychedelic note, they depart.

The Doctor, wearing a silver uniform, checks on the input from several screens and then reports back to his master, Robot X. At the end of his duty shift he is addressed as Hegg and changes into the Plistra, a garment favoured by the artisans of Planet Krill. He leaves the building and travels on a moving sidewalk like the rest of the brainwashed population. Robot police, armed with Truth beams, scan them. Two robots intercept the Doctor and drag him into a service tunnel. They remove their heads to reveal that they are Jamie and Victoria. They tell him how they have been searching for him for days since he disappeared. He looks at them blankly and insists that he is 'happy as Queeg'. Jamie takes off his own ray-foil helmet and gives it to the Doctor who comes to himself slowly but with no memory of the past few days. Victoria tells him that the robots are using mind-control rays. Angry, the Doctor steps back onto the walkway and returns the way he came. He is followed by two robots.

He enters the Robot Controller's room and tells it he has come to end the robot's rule. At first it tries to double the strength of its mind-control ray but the ray-foil helmet wards this off. Next, it shoots him with a death ray but the Doctor walks on untroubled and pushes it over. Jamie and Victoria enter and the three of them pass through a door. There they find Queeg - a giant brain in a jar. It tries to tussle with the Doctor mentally and destroy him with Brain Power until he fights back. His mental strength kills it and the travellers go out onto the street to tell the people that the rule of the robots is over.

Victoria has been alone in the TARDIS for three hours, watching the snowy landscape of the Planet Pendant. Eventually, the Doctor and Jamie reappear in the distance. They seem miserable and reluctant to enter the TARDIS. Victoria throws the door open but instead of coming in they tell her to come out and meet the friendly inhabitants of the planet - the Cogwens. She puts on a white Arctic coat and follows them. Something is odd about her friends: the Doctor tells her to leave the TARDIS door open, neither he nor Jamie talk to her and their manner is glum. She decides to test whether they have been brainwashed by lying down in the snow and becoming invisible to them. The response is startling to her: both the Doctor and Jamie pull their clothes aside to reveal that they are robots with radar tracking devices. She runs away and the robots pursue her.

She manages to outrun them until she is blocked off by a furry creature with razor claws that towers over her. It slashes at her but she pulls a bottle of perfume from her pocket and flings it in the creatures face. The bottle shatters, the creature flees in agony and the robots turn to chase it up an ice wall. Victoria realises that they were following her scent but now have locked onto her perfume. The robots slip off the ice wall and crash to the ground, disintegrating on impact.

A sound draws her attention and Victoria turns to find four squat figures pointing their weapons at her. Far from being enemies, however, they say that they are Morogs, the outcasts of the planet, and ask her to help them fight the Cogwens. They are impressed because they think she destroyed the two Cogwens. Ylit, one of the Morogs, says that he has led his men against the citadel of the Cogwens but their heat-ray weapons are useless against the robots except at close quarters.

Victoria puts together a plan. She gets the Morogs to send a message to the citadel as if it were from the two destroyed robots. It tells the Cogwens to come to the TARDIS. When a party of robots duly arrives they fail to break open the TARDIS doors and decide to take it back to their citadel. Once again, they fail to break through the doors until suddenly an army of Morogs pour out, driving the robots back into the citadel. Victoria makes her way through the corridors, dodges one robot guard, and finds Jamie and the Doctor strapped to couches. She frees them and they race back to the TARDIS. As the Doctor sets the controls to leave, Victoria sees Ylit emerging victorious from a doorway. The battle is over and the Morogs have won.

The TARDIS lands on a beautiful, verdant landscape. The Doctor tells Jamie and Victoria to come out to enjoy the sunshine but no sooner have they done so than all three begin to shrink. They are quickly dwarfed even by the ants in the grass and everything goes dark. Then, alarmingly, they are lit by what seems to be hundreds of suns. When they comment to this effect they are scoffed at by a party of old men. One of them, Hrad, suggests that this time it is a party of clowns who have come through. He says that they cannot help. The Doctor immediately asks what sort of help is needed. Hrad says that the best brains from Earth have not been able to solve the problem and life is so short nobody is likely to.

Hrad mentions going to the Glass. When the Doctor asks him what this means Hrad gives two answers. One is that the Glass is the heavens and everything in them. The other is that the Glass is a five hundred inch reflector which is not large enough. Twelve generations have been grinding a six hundred inch lens and are nowhere near completion. The Doctor queries this use of 'generations' and is told that people live for around six months there. When Hrad says that there are two hundred 'suns' in the sky the Doctor corrects him, saying there can only be ninety.

The Doctor calls the people there Microtron Men but Hrad insists that they are 'Britons' which Jamie finds odd. The Doctor replies that they are only a few yards from the TARDIS and at the same time millions of miles. He asks to be taken to see the Glass because he needs to get Victoria and Jamie away as quickly as possible before they age and die. Hrad, now convinced that the Doctor is a scientist, leads them to the lens. It is, as he said, a huge refracting lens with an object mirror in a grass hut beneath.

Entering the hut, the travellers find a group of white-bearded men. The leader, Brun, says they were of farming stock originally. The Doctor asks if they have heard of nuclear physics but none of them has. He tells them they need to expand their universe outwards, and quickly, if they are to solve their predicament. He hears them talk of vague shapes in the heavens and says to Jamie that there is nothing he can do for these people. He wonders how the men 'out there' can do this to people. All of this is a mystery to Jamie.

Abruptly, the 'suns' in the sky spin faster. The Doctor mutters that they are electrons in a radioactive atom. Suddenly all three of them are standing by the TARDIS. The Doctor shakes his fist angrily and says that the great glass the men spoke of was a microscope lens in a laboratory. He decides to leave a world like this where men can mistreat their fellows so badly.

The TARDIS lands and Jamie and Victoria are still sleeping soundly after a gruelling adventure in the 'G' galaxy. The Doctor tiptoes out of the door to investigate the new planet. He is distracted by three moons in the sky and tumbles down a hole. However, he slows down as he falls and lands gently inside a circle of ten soldiers all pointing guns at him. Their leader is humanoid but the others are doglike. They wear helmets emblazoned with a cog-wheel inside a sun. Although he Doctor says he is a traveller who comes in peace, the leader accuses him of being sent by Kanulf to kill Mufl.

Hey take him into a transporter car which races off to a city of tunnels peopled by humanoids and policed by dogs. The Doctor is led to a sterile room where he is attached to a mind reading machine. He tells the attendants that he comes in peace but the response by the officer who captured him, Captain J'nk, is to dismiss everybody else and increase the power. The Doctor hears his captor saying that he must do exactly as he is told and then he briefly passes out but when he recovers J'nk says he is convinced that the Doctor has not come to assassinate the leader, Mufl. He adds that Kanulf is the leader of the Hiinds. The Doctor says he would like to meet Mufl and J'nk replies that this has already been arranged.

The Doctor is led to the palace where he will have an audience with the leader of the planet Vegan. He enters alone through high security systems. On arrival in the oval room at the heart of the palace he finds Mufl to be a thoughtful and gentle man. On a star map in the ceiling, Mufl shows him the 843 worlds that make up the empire. Of the fourteen races that populate these worlds only the Hiinds are disloyal, hence all of the elaborate security.

He details the various assassination attempt, all foiled by J'nk. The Doctor says that there is something troubling him and asks if he may play his music pipe. The leader accedes but no sooner has the Doctor begun playing than the music causes Mufl to go into a trance. The Doctor suddenly remembers that J'nk used the machines in the answer room to hypnotise him and instruct him to kill Mufl. He searches his pocket and finds a ray gun has been put there for this purpose. At that moment, J'nk enters and assumes the murder has been done. He congratulates the Doctor and says that his task is finally complete. As he takes the gun, the Doctor plays his pipe again and the captain passes out. Mufl rouses himself. He says that he heard the whole plot and now sees that there never was a conspiracy by Kanulf or the Hiinds to kill him. He thanks the Doctor who says he must get back to the TARDIS before his companions wake up.

The Doctor and his two companions, Jamie and Polly (or is it Victoria? See note) arrive in a jungle near to a deserted village. A giant carnivorous plant attacks Polly but they manage to free her. They travel through the jungle where they soon encounter the local natives who tell them that the plants are called Kraals. When the Doctor learns that the planet has no winter season he surmises that the natives have never needed to discover fire. He uses fire to burn all of the plants around the village and then teaches the natives how to make fire so that they will always be able to defend themselves. The travellers return to the TARDIS but the Doctor is worried because he recalls that when the people of Earth discovered fire they became aggressive and this led to the discovery of war.

Note: Although the girl is named as Polly she is clearly Victoria, drawn from her television likeness.

After the TARDIS lands on an island in the middle of a swamp the Doctor tells Jamie and Zoe that they have landed on Earth in the Jurassic period. Jamie is puzzled when he sees a Tyrannosaurus carrying a gun but the Doctor tells him that no one knows what the dinosaurs were actually capable of. Zoe asks if there were men in the time of the dinosaurs. The Doctor tells her there weren't, prompting her to ask who is approaching across the swamp in a small boat.

Three ape-like men, each about three feet tall, get out of the boat. The Doctor is fascinated: no records of such creatures exist. When the three 'men' start to poke them with sticks Zoe asks if they can get back into the TARDIS but the Doctor suggests that they get in the boat with the men so that they can study them more closely. He is delighted to see that the boat even has an engine. As they cross the swamp a plesiosaur raises its head. One of the 'men' raises his stick and shoots its head off.

On the banks the men and the travellers climb aboard a stegosaurus which takes them through the jungle to a dugout. The trio are taken below ground where another ape-man accuses them of being spies for their enemies in the south. He says that this is the chance to find out what the Kabokos are planning. The trio of time travellers are chained to a wall. The Doctor can only be amazed by these advanced 'men' with energy weapons and trained soldier dinosaurs.

Eventually they are taken back to the surface and told that the Kabokos are invading Kekokro. Again they are accused of being spies and told that if they don't give up information they will be killed. They watch in amazement as two armies of dinosaurs clash, many with ape men on their backs. As the forces of Kekokro are driven back, Jamie sees his chance. He and Zoe drag a protesting Doctor onto the stegosaurus and ride back to the swamp.

Although the engine is totally unfamiliar to the Doctor he gets them across the swamp back to the island. As they scramble out, the boat is cut in half by an energy ray fired by an ape-man on the back of a pterodactyl. They get into the TARDIS just as the pterodactyl slams into the side. The Doctor is sad to leave a place of such marvels behind but thinks it is better to go to somewhere more peaceful.

No sooner have the Doctor, Zoe and Jamie stepped out of the TARDIS than they are trapped by fast-growing crystals in the form of stalactites and stalagmites. Every time they move more crystals grow around them. The temperature is dropping quickly as the Doctor tries to drag the other two back to the TARDIS but the door is completely blocked. The Doctor and Jamie shout at each other angrily about their predicament which has the effect of driving the crystals off. Soon all three are bawling to clear a path. They gety back into the TARDIS but find that, because they left the door open, the interior is full of crystals. Jamie retrieves a tape recorder and plays it at full volume. The crystals melt away.

They begin to mop up the puddles left behind. Then the Doctor hears a cry from outside and they realise that Zoe has been grabbed and dragged back out. Jamie tells the Doctor to stay in the TARDIS and keep it free while he tries to rescue her. He sets off with a portable tape player and a spanner to smash his way through.

The Doctor shuts the door after him. Almost at once he feels the TARDIS being shaken. He looks at the scanner and sees that the ship is being moved by the crystals.

Jamie closes in on Zoe and has to dash through a curtain of red flames that don't burn. Zoe is being accosted by featureless creatures like lumps of dough. He drives them off with his spanner and then drags Zoe back through the flames. The crystals have gone from the other side but so has the TARDIS.

When the Doctor opens the TARDIS door he is in a vast cavern full of crystals. At the centre is a larger crystal - the king he thinks - and on the edges he sees Jamie and Zoe. Suddenly, the crystals start to sing. Somehow the Doctor discerns meaning in the song; the crystals are singing in chemical symbols. He realises that they are singing the components of the human body. The meaning is clear - the crystals intend to eat their victims and use the chemicals for growth. The Doctor shouts this out to Jamie who sings and smashes his way through with Zoe. At last the three are united and step into the TARDIS. The Doctor sets the controls and they depart.

The Doctor takes Jamie and Zoe to Venus to visit an old friend of his, Doctor Vane, in his Experimental Botanical Gardens. Vane has some seedlings brought back from the Galea Galaxy, which sound interesting to the Doctor and Zoe but not to Jamie. However, when they arrive, the Doctor tells Zoe to stay at the TARDIS to hold the fort while he and Jamie go on to the gardens. On the way the Doctor tells Jamie that they are here to investigate some strange happenings. A few days earlier, Doctor Vane found his laboratory wrecked and his prized Galea Tentipocus plant missing.

He recounts this story to the Doctor and Jamie, adding that he has sent his assistant Regan after the thieves. Regan follows a trail and discovers large sentient plant that attacks him. The Doctor is puzzled because the tracks left behind in the laboratory suggest that a large shrub has been dragged out but Vane says that the missing plant is quite small. Hearing Regan's cry, the Doctor, Vane and Jamie rush to help. Regan tells them that the plant has grown to monstrous size and is now violent. By the time Jamie and the Doctor find the plant it is enormous. As the plant surrounds them the Doctor sets fire to it. The plant burns quickly and the travellers return to Zoe to report what happened.

The TARDIS lands on a large metal globe that is hovering above the Marie Celeste. The sailing ship is behaving oddly, shooting straight up in the air. The Doctor decides to get out of the TARDIS to investigate. Despite some misgivings, the three of them look for a way into the globe but they are pulled in by a force beam anyway. Inside, on the other side of a glass screen, two aliens observe them. The aliens, Eretz and Lanti, are disappointed that the creatures they have found are all air-breathers and they have plenty of specimens of those already. They decide to keep these three anyway and move them into a room already filled with the crew of the boat below. The Doctor tries to explain that they have been captured by aliens from beyond the stars but these words mean nothing to them.

The Doctor and Jamie take a marlin spike each from the sailors and break the glass window which releases clouds of green glass. The two aliens writhe in agony as the humans crawl through the window and past them into the body of the ship. the TARDIS is inside now but the Doctor has mislaid the key. He tells the sailors that their salvation is in the box and that there is room for all of them. They think he is mad and back away.

The space-ship falls, out of control, into the sea where it is crushed in the coils of a giant sea serpent. The Doctor remembers that he left the key in the lock and opens the door. He dashes into the TARDIS and starts the engines. Jamie and Zoe implore the others to join them but they prefer to die of the poisonous gas breathed by the Arcturians or at the jaws of the serpent. As the TARDIS whirls away across time and space the Doctor comments that nobody will believe their tale about the fate of the crew of the Marie Celeste or the existence of giant sea serpents.

The TARDIS has just made an emergency escape from the robots of the nightmare planet Korad but the space time locator has been damaged. The Doctor lands the TARDIS in order to make repairs and the travellers find themselves on a planet of snow and ice. A single moon is in the sky. The Doctor sets about making his repairs while Jamie and Zoe put on Atmospheric Density Jackets and take a walk to a nearby glacier. A sudden wind whips up the snow so that they can't see their way back to the TARDIS and both of them are blown off their feet towards a crevasse.

When the Doctor finishes his work and steps outside there is no sign of his companions. The absence of footprints tells him that there has been a storm. He walks to the crevasse and finds one of Zoe's buttons in the snow. He can also discern another button on the other side of the crevasse so he crawls over a fragile snow bridge to get to the other side. The bridge collapses behind him, cutting him off from the TARDIS.

He walks on until he comes to a valley containing a small, deserted city. He enters the city and goes into the nearest building. In the entry hall there are six sets of stairs. Five are still but one is moving so he steps on. It takes him to a vast store room whose shelves are lined with glowing cubes. When he touches one it speaks to his mind, saying that these cubes are all that is left of the Morrains. The cube tells him their sad story: the sun died and the people built a city, Glace, as defence against the encroaching ice. When it became obvious that their plight was hopeless the leading scientist, Cosmos, suggested turning the people into cubes while he remained as their guardian. Only when this had been done did they realise they had been double crossed and Cosmos was going to use their thought energy to power a ship that would take Cosmos away from the planet. Unfortunately, he didn't have enough power to escape but now he has two new people to add to his reserves.

The Doctor realises that Jamie and Zoe are in terrible danger and takes some quick advice from the cubes. He finds a flying scout car and launches himself into the sky. He sees that there is a tower in the centre of the city, the only building showing a light. He lands on the roof of the tower. Floodlights come on and huge robots advance on him but he uses the car's weapons to blow them to pieces. He takes an elevator to a laboratory where Jamie and Zoe stand motionless in cubicles.

Cosmos enters behind him and the Doctor turns to see a three-armed humanoid carrying a gun. The Doctor offers to replace his companions and become the most powerful cube Cosmos could dream of. The Morrainic scientist eagerly agrees. The Doctor tells Jamie and Zoe to take the scout car on the roof back to the TARDIS. Zoe is reluctant to leave but Jamie tells her that he is sure the Doctor has a plan. They wait beside the car and soon there is an explosion below them. The Doctor quickly emerges and tells them that his ability to reverse his thought processes blew up the evil scientist and his equipment. Jamie flies them back to the TARDIS.

The TARDIS lands under a palm tree on a long tropical beach. The Doctor tells them that they are on the planet Delffo in Galaxy G. He has come to visit a friend of his, Toofo, the leader of an amphibian race called the Creels. He warns them not to trust the planet's beauty and as a demonstration he holds his musical pipe out to a flower which promptly bites at it. He returns to the TARDIS to consult his maps and declares that they are on the Island of Devils. While he sets the coordinates to hop them around the planet, Jamie states his intention of going for a swim. Zoe runs out to warn him that the Doctor might go without him but there is no sign of the young man.
Zoe calls the Doctor and together they discover his footprints. However, these end suddenly next to a single giant print and a scrawled message that says Jamie has gone with Man Friday to meet the devils in the mountain. The Doctor locks up the TARDIS and leads Zoe into the jungle. They stop by a river to get a drink. Zoe looks into the water and sees a strange creature with an eel-like body and a near human face. The Doctor tells her it is a Creel. This creature recognises the Doctor and introduces himself as Goruf. He tells them that he saw a Blikk carrying a young man and gives them directions for where he thinks Jamie will have been taken. The Doctor asks Goruf to report back to Toofo and asks for some help to be sent to rescue Jamie. Goruf offers them his pistol to fight the Devils but the Doctor asks if the Devils are known to be violent. The Creel admits that there is no record of violence but the Devils are so ugly his people don't trust them.
The Doctor and Zoe cross a field of flowers that they have been warned have a deadly scent. They stumble out of the other side and a giant robot lands next to them. It asks them to accompany it to meet Jamie. They agree and the robot - Man Friday - flies them to the mountains and down a tunnel. It deposits them in a hall containing a horseshoe shaped table. Seated around it are black, misshapen figures. They welcome the travellers to the Hall of Shadows.
The leader, Murko, tells the Doctor that his people used to dwell in a volcano. When it became extinct they were forced to the surface to get their energy from the sun. Their eyes, unfortunately, are too weak and so they have to stay in the dark. The Blikks are sent out to gather news of the world outside. Jamie steps forward to vouch for this and the Doctor and Zoe realise that the arrival of the Creels to rescue him will, in fact, lead to a new friendship between the two peoples. Beauty is only skin deep.

The Doctor is woken up in a prison cell and led by an armed guard to the Great Hall. The Doctor is subservient, his mind a blank, as he thinks that he must obey Dorak and serve Shran. In the Great Hall, giant cockroaches are working as slaves to build a space ship. They are overseen by cruel men in metallic suits. The Doctor is taken to the leader, Dorak. After making the Doctor play a tune on his pipe he tells him that the god Shran has new orders for him.
Shran is a computer that reveals how the space ship crashed and the native species were subjugated. The Doctor was found wandering on the planet, his mind wiped and he was put into slavery. Now he is told to create an atom bomb to blow the planet apart when the Garvanes leave.
The Doctor is taken past the natives ruined homes and demolished vehicles. An airship is tethered there. Dorak takes him to a laboratory and instructs him to complete the bomb quickly. One of the cockroach slaves trips a guard and takes his weapon before killing both Dorak and him with it. The guard dies firing wildly, hitting the Doctor. He slumps to the floor but recovers. The cockroach says he is Ekk of the Shelgars and he was only pretending to have been hypnotised by Shran. The Doctor remembers landing the TARDIS in a giant bird's nest and leaving Jamie and Zoe asleep while he explored. He was caught and enslaved for eight days.
He tells Ekk that he will wire up the bomb so that if any of the Garvanes try to complete it they will be blown up by it. They then use the ray gun to shock more Shelgars out of their trance. They pass the gun on so that more slaves can be freed. Ekk and the Doctor steal the airship and fly off to the mountains. They are attacked by a flock of giant birds. Ekk shoots some with arrows and the Doctor kill another with a spear but the balloon is punctured. They crash near the nest containing the TARDIS. A Garvane scout ship lands nearby and the guard is about to kill both of them when Jamie appears from above and throws a boulder at him. The guard is knocked senseless. The Doctor and his companions retreat to the TARDIS and Ekk takes the scout ship back to join his people in the battle for their freedom.

The TARDIS lands, 5000 years in the future to find Hope City in ruins. Jamie speculates that the city was destroyed by atomic bombs and the Doctor suggests they try to find some records. Unknown to them, they are being spied on by a robot that hasn't seen a human for a thousand years. They split up and Zoe is soon captured by the robot. Jamie falls prey to it soon after. Finally it confronts the Doctor. It tells him that it has read the minds of his companions and knows who he is. He reminds it that robots are the servants of mankind but the robot pronounces itself the Robot King. He says that humans are too irresponsible to be allowed to live and attacks them. As he lifts the Doctor up to throw him to his death the Doctor spots the King's off switch and ends the threat. Zoe tells the Doctor that he was 'switched on' when he thought of that.

When Jamie turns on the scanner to see where the TARDIS has landed the world outside is dark. They realise it is a jungle gloom. They see an ape-man wearing a tool belt. It appears to be carrying an old Earth-style blunderbuss. Jamie doesn't fancy going out but the Doctor and Zoe put on contra-gravity suits and leave the TARDIS. They hover through the trees until they catch up with the ape-man who uses his 'weapon' to cut the power in their suits and paralyse them. They land heavily next to him. The Doctor and the creature converse, using the Galactic dialect. He says he is Valgar, the Chief Guardian, and he is taking them to the City of Menrox to dissect them. He suspects that they are Jaiboh robots.
He brings a sledge out from the trees and hoists them onto it. They speed off to a beautiful crystalline city. The travellers are carried to a laboratory and freed from their paralysis but trapped inside a force-field. They are scanned by a machine that proves they are neither robots nor Jaibohs. Valgar decides to cut them open. The Doctor does not translate any of this to Zoe. Instead, he pulls out his pipe to play a tune. The effect is devastating; the ape-men flee in panic, the alarms are sounded and the force-field is switched off. The two prisoners leave the room where they are shocked to find Jamie waiting for them.
Jamie says that he saw them being captured so he hopped the TARDIS nearer to the city and then put on a contra-gravity suit to come and rescue them. They fly out of the city but realise that hundreds of the hover sledges are disgorging from a tower. They are not chasing the travellers, however, but launching into a battle with Jaiboh space ships. As a battle rages the travellers follow a trail of thread that glows in the dark which Jamie has left through the jungle.
Just as they reach the TARDIS, Valgar speeds at them on a hover sledge but the Doctor plays his pipe and Valgar falls off, screaming. The trio enter the TARDIS which soon dematerialises.

The Doctor is lecturing Jamie and Zoe about the plurality of universes. As he does so, the TARDIS lands on a planet with two suns. The trio emerge and begin to fly up into the air. They are delighted but, almost immediately, they are caught in a giant net. The Doctor passes out. When he wakes up he is in a metal room that smells of oil. On the far side of the room are men with three eyes (one in the back of the head), four arms and wearing metallic suits. The aliens are delighted with their find: never in their travels through the dimensions have they found creatures so similar to themselves. When the Doctor speaks to them they welcome him and say that all creatures that are useful to the Life Force are entitled to live. They reassure him that Zoe and Jamie are safe.
The Doctor realises that the three eyes are actually holes in a helmet and the extras arms are mechanical. He floats to a high window and notices that the room he is in is moving across a landscape. The room lurches to a halt and the creatures take him out of the door. He is gripped by one of them and together they fall to the sandy surface. He sees that he has come out of a tall metal tower. Others like it are moving slowly across the landscape. Another creature says that he has traced Jamie and Zoe as natives of the Five Hundred and Third Universe. He wonders which Door they used to leave it. The Doctor says they did not use a door and tries to explain the TARDIS.
One of the aliens interrupts and says that they came from the 8, 091st Universe. They found the travelling machine abandoned there and were about to leave the planet when the Doctor arrived. Another alien proposes they just kill the travellers and leave but a third disagrees. He says they should examine the travellers before they kill them. He seems to feel that oxygen breathers are incapable of rational thought. The Doctor demands to know what the aliens mean by 'doors'. They tell him that they are the points where universes touch. They have discovered 1001 doors and each time they pass through one to an oxygen universe they explore and then seal the door forever after they leave.
The Doctor punches the glass helmet of one of the aliens. He is astonished to see that the creature is a vortex of something slimy and sticky. It burns up in the oxygen atmosphere. While the other aliens are too shocked to respond the Doctor and his friends run to where the TARDIS is standing nearby. They enter quickly and shut the doors. Jamie begs to leave before the TARDIS is vaporised but the Doctor reassures him that the ship is invulnerable to any weapons. Nevertheless, he sets the controls for their departure.